I'm trying to find a word that describes a lack of confidence. Something that gives a sense of worthlessness maybe. I've dried looking up in Thesarus.com for similarities to lack of confidence and antonyms to self-worth, but with no luck. Anyone have some ideas?

I think wavering (“Fluctuating; being in doubt; undetermined; indecisive; uncertain; unsteady”), faltering (To “be unsure or weak” or “Move hesitatingly, as if about to give way”, etc.), and irresolute (“Undecided or unsure how to act” or “Indecisive or lacking in resolution”) might serve.